This invention relates generally to fluid filters and, more particularly, to a fluid filter element which is adapted to be precisely folded for use in a sealed pan, or the like.
A wide range of filter assemblies have been used in filtering various fluids, such as transmission fluids in the automotive industry. An increasingly popular filter assembly utilizes a filter element which is generally flat and folded upon itself for receipt within a relatively flat, sealed "pan" having inlet and outlet ports. The relatively flat pan reduces the overall dimensions of the filter assembly and, therefore, can fit in compact space environments. The pan normally has a desired peripheral configuration, with matching halves for containing the folded filter element. Likewise, the filter element normally has a pair of opposed ends, usually of identical configuration, whereby the opposed ends are folded back upon themselves for receipt within the complementarily shaped halves of the sealed pan. Flow-through passages also are cut in the filter element complementary to the ports of the pan.
Normally, a fold line is formed intermediate the opposed ends of the filter element to facilitate folding the element upon itself. However, heretofore, the fold lines have been formed by singular linear indentations in the filter elements which do not lend themselves to precise folding which would enable the identical or complementary opposed ends of the filter element to be folded precisely. Often, the fold line is uneven, or inconsistent at most. This causes the opposed ends of the filter element to be distorted or out of alignment, making it difficult to insert the folded filter element into registry within the matching halves of the filter pan, as well as causing improper sealing of the pan.
This invention is directed to solving the above-identified problems.